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COMMENT: Bt cotton found susceptible to army worm in Sindh
The Bt cotton is a genetically engineered crop in which a synthetic version of gene from the soil — Bacterium bacillus thurigiensis — is inserted so that the plant produces its own Bt toxin to kill the pest.
Spray preparation of the bacteria containing the toxin have been used for decades by organic growers, integrated pest management practitioners and other farmers interested in sustainable agriculture. Bt is one of the most valuable pest control tools for such farmers.
In Pakistan, Bt was got registered as early as the seventies by a leading agrochemical producer, Sandoz. Later, Pak Agro Chemical had the Bt registered with the department of plant protection of the government of Pakistan. But Bt products failed to create a market in Pakistan because of several factors including inefficacy under harsh climatic condition during the cotton season.
In 1995, despite considerable protest from environmentalists and organic farmers who were concerned about insect resistance to Bt Environmental Protection Agency (EPA) of the United States registered three Bt crops — corn, cotton and potato.
In the year 2000, a local newspaper of Karnataka (India) reported a secret trial of Bt cotton by American agri-business giant Monsanto.
Fearing genetic contamination through cross-pollination, farmers in Karnataka had then taken torching fields in which the Bt cotton trials were carried out secretly.
However, on Feb 7 this year, according to Sci.Dev.Net, yields of a genetically modified cotton crop planted in India have shown an 80 per cent increase over other similar crop during the period studied by a group of German university students. Reportedly, the Indian government has now approved the cultivation of new GM variety of Bt cotton.
In Pakistan too, according to the Consumer Protection Network, Islamabad, Monsanto is aggressively lobbying Pakistan government to get clearance for its “controversial” Bt cotton for large-scale cultivation and marketing, claiming that the transgenic variety is environmentally safe and economically lucrative for the farmers.
It would be appropriate to mention here that, like in other part of the world, environmentalists and consumer rights groups in Pakistan have mounted protest against the introduction of transgenic crop varieties into farmland, fearing that such a crop will have severe impact on the environment and human health.
On the contrary, Monsanto claims that the Bt cotton is genetically enhanced to resist major caterpillar pests, including the tobacco boll worm (the army worm), boll worm and pink boll worm.
In spite of the fact that the National Institute of Biotechnology and Genetic Engineering had prepared a voluntary code of conduct for the release of genetically modified seeds in 1994 to 1995, a national bio-safety expert committee formed by the government prepared bio-safety guidelines.
From 1999 to 2000, a draft bio-safety guidelines was prepared by the subcommittee, while in 2001, a final consultation with all the stakeholders was recommended for adoption of the laws.
Ironically, in defiance of the code of conduct and safety guidelines, Bt cotton was illegally cultivated on vast acreage both in the lower and the upper Sindh during the Kharif 2002 season. Initially, cultivation of the Bt cotton was undertaken probably with the seeds smuggled from the neighbouring India.
Observations of Bt cotton fields, undertaken by this writer during 2002, had indicated its high susceptibility to the jassid (Empoasca devastans) and mites, though the mite insurgence in case was probably because of repeated sprays of methamidophos. Beside jassids, Bt cotton was also found highly susceptible to cotton leaf-curl virus (CLCV).
This year (Kharif 2003), cultivation of the unauthorized Bt crop was again observed, despite the ban by the agriculture department of the government of Sindh, in district Ghotki, taluka Rohri in Sukkur and taluka Nara in district Khairpur.
In district Ghotki, about 2 acres at deh Bakra and about 4 acres at deh Darveish in taluka Mirpur Mathelo was found heavily damaged by the armyworm.
The most haunting aspect of the Bt cotton damage by the armyworm was an extremely high susceptibility of all parts of the Bt crop — leaves, squares, flowers, and immature bolls.
The extent of army worm susceptibility to this crop could be gauged from the fact that a single flower along with its sepals was found harbouring 2 to 10 first and second instar larvae of armyworm.
This observation contradicts the claims of Monsanto as well as the supporters of Bt cotton (“No place for pests in Bt cotton” in Dawn Sciencedotcom: Nov 1).
Another plot of Bt cotton at deh Panwar in taluka Rohri, district Sukkur, was also found to be badly damaged by the army worm despite three sprays of pesticides as apprised by the grower concerned.
However, a one-acre plot of Bt cotton at deh Sikandrabad in taluka Nara of the Khairpur district was found free from armyworm damage. But this happened probably because the entire area was free from any army worm insurgence.
According to the owner of this Bt crop, he had applied three sprays for the control of the jassids.
This scribe has observed that during the past two Khareef seasons, Bt cotton was found to be susceptible to such pests as jassid, army worm, and cotton leaf curl virus (CLCV) at least under upper Sindh climatic conditions
Suggestions: In the light of facts and observations mentioned above, it is strongly suggested that under no conditions should cultivation of Bt cotton be allowed in the country, particularly in Sindh where its cultivation, though illegal, has been tried and found highly susceptible to pests and diseases.
The writer
Case against genetic cotton
The Genetic Engineering Approval Committee set up by the government of India deferred the commercialization of Bt cotton in India in 2001. The reason for this, as given by GEAC Chairman A. M. Gokhle, was: “the technology is new to us, we did not want to take any chance.” GEAC suggested that large-scale trials need to be conducted in different agro-climatic conditions first.
Prestigious Indian newspaper, The Hindu, in an editorial (Sept 6, 2001) comments on the case in these words: “experience over the last five years reveals problems that place a question mark on this entire approach to pest control. In fact, there is growing concern that the very effectiveness of Bt as a bio-pesticide could be irrevocably endangered if use of Bt-transgenic plant varieties is not stopped immediately. Rigorous field studies of teams led by Bruce Tabashnik (University of Arizona) and Fred Gould (North Carolina State University), both reported in recent years in the Proceedings of the National Academy of Sciences, US, provide solid evidence of insect resistance to Bt cotton.”
The editorial further says, “Since resistance has become a major worry, companies now insist that farmers follow resistance management plans (RMPs), which include ‘refugia’ (keeping a certain proportion of fields free of Bt seeds and insecticides).”
The editorial, penned by Director, Baba Amte Centre for People’s Empowerment, and Secretary, Samaj Pragati Sahayog, both based in Madhya Pradesh, contends, “Field data show that expression of toxins in Bt- transgenic crops can develop unevenly in different parts of the plant. In one report, Bt toxin expression was found to be 90-95 per cent in the top part of the plant but only 20-25 per cent in the lower nodes, making them more susceptible. Since the lower nodes often produce the highest quality cotton, their loss is even more significant.”
Even in the United States, powerful demands are being made that the EPA should delay any further approval of Bt- transgenic plant varieties, and that previous approvals should be reversed when evidence points to imminent failure of an RMP. The EPA had granted only conditional registration to Bt crops in 1995. The EPA approved its use in May 1998 only as animal feed and for industrial purposes. In April 1999, AgrEvo again petitioned the EPA to permit use of StarLink for human consumption. The EPA set up a Scientific Advisory Panel (SAP) comprising 16 physicians and independent scientists to advise it on the matter. In its report to the EPA in December 2000, the SAP concluded, “there is a medium likelihood that Cry9C protein is a potential allergen,” thus rejecting the use of StarLink corn in human food.
In spite of these reports from India and the United States, one wonders why some people want to promote use of Bt cotton in Pakistan. — M. Khalid Rahman
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